Improvement in the manufacture of tin cans



Unirse drames EDWARD T. COVELL, OF BROOKLYN, NEW YORK.

IMPROVEMENT IN THE IVIANUFACTURE OF TIN CANS.

Specification forming part of Letters Patent No. 412,35H, dated April19, 1864.

improved cans with its top off; Fig. 2, a transverse section of thesaine; Fig. 3, a vertical section of the same with its top in place; andFig. 4, a vertical section of a part of the bottom and one side of oneof my improved cans, showinga mode of' securing the bottom thereindiffering somewhat from that illustrated in Fig. 3.

Similar letters of reference indicate like parts in all of the figures.

The object of my invention is to afford a simple, expeditious, and cheapmode of uniting with each other the sides and ends of a sheet-metal can,and by the employment of this mode to produce a neat and strong can.

Heretofore in the construction of such a can as is illustrated in theaccompanying drawings the usual process has been to lap the margins oftwo opposite sides-such as A and around the edges of the other two sidesand to complete the joints by running a seam of solder over each one andon thesurface of the can, after which the end sheets,which are madelarger than the transverse area of the can, are placed in position andtheir margins lapped over upon the outside of the can and also soldered.The can as thus constructed is not only unsightly and not very strong,but it also requires great skill and care in its construction, as theedges of the sheets of metal being exposed to immediate contact with thesoldering-iron the solder, unless run on very quickly and skillfully, isapt to penetrate unequally under the edges and cockle7 them, thusforming an irregular and clumsy joint. I overcome these difficulties andobjections by forming the joints of the cans as illustrated in theaccompanying drawings, the formation of the sheets composing the sidesof the can being most clearly shown by Figs. 1 and 2,

wherein it appears that one margin 0f these sheets is bent inwardlyuntil it reaches a position approximating to a right angle with thesheet, while the opposite margin thereof is bent into such a form asthat its transversesection is somewhat similar to the letter Z or figure2. These sheets. being so bent, are placed in such positions relativelyto each other as thateach simple bend of the sheets may be received intoand in a degree embraced by the compound bend of the next adjacentsheet, and being in this position it will be observed that a gutter orgroove is formed at each angle of the can, down which the soldering-ironmaybe guided with ease and accuracy by even an inexperienced hand, andas the edgesof the sheets are not exposed to direct contact with theiron the liability of cockling the edges is overj come.

The heads may be secured in the can by simply turning up a flange oneach edge thereof and insideof the can, after which they are solderedsecurely on the outside of the joint, or they may be secured in themanner represented in Fig. 4, Here a groove is formed on vthe inner faceof each side of the can, and before the sidesfare soldered together theheads, previously prepared of a proper size and hemmed, if desired, areplaced in 4such a position that each edge thereof is received into oneot' the grooves, after which the whole is soldered together.

The side plates of the can may with advantage be hemmed at top andbottom.

I am aware that the joints of sheet-metal cans have been made by turningin the margins of the plates at suitable angles and soldering togetherthe outer faces of these turnedin margins; but it will be readilyperceived that the joints constructed upon my plan are much strongerthan these, and have the ad ditional advantage of being free from thoseinwarwadly-projecting sharp ribs which are found in cans constructed asaboved escribed, and which are liable to injure the contents of the can.

My improved cans are more easily constructed than those made on otherplans, as from the peculiar' formation of the several plates each is ina measure tied in place by the two next adjacent ones even before thesolder is applied.

Having thus fully'described my improved A manner of constructingsheet-metal cans,what I claim as my invention, and desire to secure byLetters Patent, is

1. Uniting the sides of sheet-metal cans by means of interlockinghook-shaped iianges and solder, substantially as herein set forth; but

this I only claim when the hook-shaped anges are completely formed uponthe margins of the side sheets before the said sheets are joinedtogether for the formation of a can, when the sides of a sheet-metal canare united with eachother by means of the above-described interlockinghook-shaped flanges and solder.

2. Securing the heads of the can in proper position by means of groovesformed inside of the can for the reception of the edges of the heads,the joints being completed by the ,use

of solder or other suitable cement.

The foregoing specification of my improvement in sheet-metal cans signedby me this 12th day of December7 A. D. 1863.

EDVD. T. COVELL.

In presence of-y Tnos. C. CAsE, SAM. SU'rrE.

